The coupling of boundary elements and finite elements for nondestructive testing applications

In this paper, the coupling of finite elements and boundary elements, referred to as BEM-FEM coupling, is used to numerically treat a nondestructive testing (NDT) problem based on eddy currents. BEM-FEM coupling is especially well suited for NDT problems because it greatly reduces the discretization effort. A general formulation for such problems involving FEM and BEM is given. The coupling of both methods is achieved using the boundary conditions on the common boundaries between FEM and BEM domains. Only the conducting parts and the exciting coil are discretized by finite elements. The surrounding air space is taken into account by boundary elements. As an example, problem no. 8 (coil above a crack) of the TEAM workshop (Testing Electromagnetic Analysis Methods) is considered.